Does positive TPO mean I have thyroid disease?

Positive TPO antibodies indicate autoimmune activity against your thyroid, but you may not yet have thyroid dysfunction. About 20% of people with positive TPO develop hypothyroidism within 20 years. Regular TSH monitoring is recommended.

Can TPO antibodies decrease?

Yes, TPO antibody levels can fluctuate and sometimes decrease. Some research suggests that gluten-free diet, selenium supplementation, and addressing underlying inflammation may help reduce antibody levels in some people.

Should I test TPO or TG antibodies?

TPO antibodies are more commonly elevated in Hashimoto's (95% vs 60-70% for TG antibodies). Testing both provides the most complete picture, as some people have elevated TG antibodies with normal TPO. The combined panel is often recommended.

I have positive TPO but normal TSH. Do I need treatment?

Generally, treatment isn't started until TSH becomes abnormal. However, positive antibodies warrant monitoring (typically annual TSH). Some practitioners consider low-dose thyroid hormone for symptomatic patients with very high antibodies, but this is controversial.

🦋 Thyroid

TPO Antibodies (Thyroid Peroxidase Antibodies) Blood Test

Name: TPO Antibodies (Thyroid Peroxidase Antibodies) Blood Test
Brand: Justlabs
SKU: 0005081
Price: 14 USD
Availability: InStock

TPO Ab

TPO antibodies are markers of autoimmune thyroid disease. Elevated levels indicate Hashimoto's thyroiditis, the most common cause of hypothyroidism in the United States.

Thyroid Peroxidase (TPO) is an enzyme essential for thyroid hormone production. In autoimmune thyroid disease, the immune system mistakenly produces antibodies against TPO, leading to thyroid inflammation and damage.

TPO antibodies are found in approximately 95% of Hashimoto's thyroiditis patients and 70-80% of Graves' disease patients. They can be detected years before thyroid dysfunction appears, making them useful for identifying at-risk individuals.

Hashimoto's thyroiditis causes gradual thyroid destruction, eventually leading to hypothyroidism. Early detection through TPO antibody testing allows monitoring and early intervention. Even with normal TSH, positive TPO antibodies increase the risk of future hypothyroidism.

Price

$14

Results

2-3 days

Lab Network

Quest

Fasting

Not Required

What's Measured

TPO Antibodies

What This Test Measures

This test measures the concentration of antibodies against thyroid peroxidase enzyme in your blood, typically reported in IU/mL. Results are classified as positive (elevated) or negative (normal).

Who Should Consider This Test

Anyone with symptoms of thyroid dysfunction, those with family history of autoimmune thyroid disease, people with other autoimmune conditions (increased risk), women planning pregnancy, those with unexplained fatigue or weight changes, and anyone with goiter.

Health Insights

Conditions Screened

Hashimoto's thyroiditisGraves' diseaseAutoimmune thyroid diseasePostpartum thyroiditis riskThyroiditis evaluation

Related Symptoms

FatigueWeight gainCold intoleranceHair lossDepressionConstipationDry skinMuscle achesBrain fog

When to Get Tested

No fasting required. Can be tested any time. If you have symptoms of thyroid dysfunction, test alongside TSH and Free T4 for complete evaluation.

Understanding Your Results

Negative: <9 IU/mL (varies by lab). Positive: Above reference range. Positive TPO antibodies with normal TSH indicates Hashimoto's risk but not current dysfunction. The higher the antibody level, the greater the likelihood of developing hypothyroidism over time.

What to Expect

After placing your order, you'll receive an email from Rupa Health (our lab order partner) within 24 business hours to sign a consent form and schedule your blood draw at a Quest Diagnostics location.

The blood draw typically takes just a few minutes. Results are usually available within 2-3 business days and will appear in your secure Justlabs dashboard.

Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.